A liquid crystal display (hereinafter, referred to as LCD) is a device which displays a character and an image using electro-optical properties of a liquid crystal molecule, and has been widely applied to a cellular phone, a notebook computer, a liquid crystal television, etc. However, since the LCD utilizes a liquid crystal molecule with optical anisotropy, there are such problems that excellent display properties are demonstrated in a certain one direction but, in another direction, a screen becomes dark or indistinct. In order to solve the above-mentioned problems, a birefringent film has been widely employed for the LCD,
As one kind of the birefringent film, a birefringent film in which a refractive index ellipsoid satisfies the relationship represented by nx>nz>ny is disclosed (see e.g., Patent Document 1). The birefringent film having such a relationship of refractive index has conventionally been produced by attaching a shrinkable film to both sides of a polymer film, and stretching the resultant in such a manner as to expand in the thickness direction. Therefore, a conventional birefringent film having the relationship of a refractive index is likely to increase in the thickness, which makes it difficult to reduce the thickness of the liquid crystal display.
Further, conventionally, the birefringent film having the above-mentioned relationship of a refractive index has the following problems: when the birefringent film is placed under high temperature and high humidity, the optical properties are likely to decrease, and light leakage is caused by the defects of an alignment property. Patent Document 1: JP 2006-072309 A